Oily Stuff on the Wall of Tank

[sungminee]

anyone know what they are?
i clean them before water change it appears again.
i feed brine shrimps and blood worms.
water change every 2-3 day with 25%

[RyanH]

Brine shrimp is pretty oily. That is probably it.

Your fish also give off slime. If you don't wipe down the glass it can build up.